Donation of Constantine

The Donation of Constantine was a forged decree by which the 4th century Roman emperor Constantine the Great supposedly gave the Pope control over the city of Rome and the Western Roman Empire. The decree was forged during the 8th century, and the Papacy used the decree extensively during the 13th century, supporting claims of Papal political authority. From 1439 to 1440, Italian priest Lorenzo Valla discovered that the "donation" had been forged, as it used anachronistic terms such as the word "fief". The discovery of the forgery severely damaged the power of the Papacy.